Improvement in geinding-mills



J, H. BEAR. GRINDING MILL. No. 61,599. Patented Jan, 29-, 1867.

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JOHN H. BEAR, 0 F YORK, PENNSYLVANIA,

Letters Patent No, 61,599, dated January 2 9, 1867. i I

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TO ALL WHOM IT MAY CONCERN:

Be it known that I, JOHN H. BEAR, of York, in the county of.York, andState of Pennsylvania, have invented a newaud improved Grinding-Mill;and I do, hereby declare that the following is-a full, clear, and exactdescription thereof, reference being bad to the accompanying drawings,making a part'of this specification,

n.\vhic-h-- Figure 1 is an elevation ofpne side of the improved mill.

Figure 2 is a longitudinal section taken vertically through the centreof the mill.

Figure 3 is a transverse section taken vertically through the centre ofthe two stones.

Figures 4, 5, 6, and 7 show the construction and forms of the runner andstationary stones.

Similar letters of reference indicate corresponding parts in the severalfigures.

The nature of my invention consists, first, in giving the runner andbed-stones a form which is a segment of a sphere in any direction inwhich they are intersected. By giving this form, the substances beingground will be'caused to keep at the centre of the concave, and willalso be subjected to a greater amount of grinding surface in a giventime between any two given points, than is the ease with a stone formedwith a right-line surface, or a surface formed of .two truncate d cones,for 'theireason that the amount of surface presented by a segment of asphere is much greater than the 'surfadepres'onted by a right line ortwo intersecting right lines, allother things being equal. I

My invention consists. second, in constructing the'run-ner stone withmetallic capsatits axis, which caps are held 'in'place by stay-pins, andwith metalli'c'hoops placed around sno'ulders "formed on its endsoutside of said collars. The collars and pins serve to connect it to arevolving shaft, and the hoops permit of its being revolved rapidlyaround withsaid shaft without'any liability of separation-0t its partsbycentrifugal action.

My injvention consists,'third, in a novel arrangement of the platform, bed-stone,and clamp, and adjusting sciews in combination with thevertically revolving runner.

My invention consists, fourth, in a. novel arrangement of a deflector."

My invention consists in a novel arrangement of the hopper with thebed-stone.

My invention finally consists in a combination of metal guards, andclamp-screws, with the runner-stone andb'ed-stone. v

To enable others skilled in the art to understand my invention, 1 willdescribe its construction andioperation.

The frame of the mill may be constructed of two upright timbers A Asuitably framed together, and sustained by two inclined legs B B, whichwill afford awide substantial base for the mill. C represents thehopper, which is secured by accommodating books 10, or other fastenings,to the-upper part of the frame A, and which is provided with a rotatingfeeder, a, for preventing the grain from, clogging at its dischargeopening. This opening through the hopper allows the grain to how betweenthe stones tobe ground, and a sliding gate or valve 6 is applied to thisopening, and moved by means of a screw-rod, b, havingh crank-handle uponit, so that the flow of-the grain from the hopper can be regulated byincreasing or diminishing the size of the discharge opening, as shown infig. 2. Beneath the hopper C is ahorizontal platform or bed, D, which issupported by the frame A. and B, by means of suspenders a cwhicharedesigned for elevating or depressing the platform and levellingit. Upon the platform D the stationary stone E is mounted andsecureddown firmlyin place thereon by means of clamping bolts 0"0, the upperhooked ends of which draw down upon metal straps a n that are upon theupper edges of the stone E. .These straps serve as a bearing for theclamping screws 0" c, and they also serve as guards to prevent theescape of the grain or meal at the sides of the mill from between therunner stone and the concave, they being arranged so as to overhang theconcave'to a slight degree, and also was to just clear the ends of therunner-stone. Their office .is to make a close joint between the concaveand the runner-stone at the sides of the mill, about'as represented infig.2 by dotted lines, and in figs. 3 and 7 in full black lines. Thisstationary stone is concave transversely, and also longitudinally, asshown in figs. 2, 3, and 7, and

its front end and rear end rise considerably above the eentre, as shownin fig. 2. The runner G is arranged to rotate in a. vertical plane abovethe stone E, and it is suitably secured to a horizontal shaft F, whichhas its bearings upon the frame legs 13 B, and which is rotated by meansof a belt passing over the drum On the opposite end of the shaft F tothe drnmf a fly-wheel J is secured, also a grooved pulley J, whichlatter rotates the feeder a by means of a belt. The runner'G iscircular, and. its periphery is convex transversely and adapted to fitsnugly into the concavity of the stationary stone E,'so that the convexand concave surfaces can be made perfectly true by grinding themtogether, after which they are set apart so as to leave the requiredgrinding space between them. By reference to fig. 7 itwill be seen thatthe stone E is picked in lines converging from its centre to its sides,whichhform channels. that have a tendency to drawthe grain and flourtoward the centre of this stone to be acted upon by that portion .of thesurfaceof the runner which has the greatest speed. If desirable, thegrinding surfaceof the runner may also be picked or grooved. The runnerG is constructed with annular elevations projecting centrally from itssides for receiving tires or bands of metal 9 9, that are heated andshrunk on said elevations for the purpose of preserving the stone frombreakingand flying ofi' while being driven ata very high rate of speed.This runner may be securedfirmly on its shaft F by means of circularclamps h hand a nut, h, which latter screws upon its shaft F, and is setup against one of the clamps. The flour escapes from its point ofdischarge 2' into a hood or cover J", and falls upon an inclined troughK which conducts it out of the mill and discharges it upon a screen in avibrating'shoe L, shown in figs. 1 and 3. As some of the flour whichadheres to the grinding face of the running-stone G will be thrown 08 bycentrifugal force, I arrange a guard at over this stone for directingsuch flour downward into the trough K. i I

am aware that it is not new to grind at the circumference of a rightcylinder working in conjunction with a concave whose surface isflatytuken transversely, and therefore I do not claim broadly grindingat the circumference of a circular rotating runner. By reference tofigs. 3 and 5 it will be seen that one of the circular clamps II issecured to the runner by means of pins 112 m inserted through tbe'clamp,and entering the stone some dis tance. These pins strengthen the stoneand prevent it from breaking. It will also be seen by reference to figs.1 and 2 that the hopper Crests upon the top of the stone E, and isattached to the frame A so as to rise and fall with the platform D,stone E, and the hopper K. And thuswhenever the concaveE is adjustednearer toor farther from the runner stone, the hopper will adjustitself'in proper position for feeding the grain to the stones.

If the hopper was supported entirely upon the frame by suspe'ndingconnections, it would benecessary to adjust it after the stone E hadbeenadjusted, and thus time would be lost, and besides this the adjustmentwould not be as accurate and perfect as when the hopper adjusts itself'simultaneously with the bed-stone or concave.

Having thus described my invention, what I' claim as new, and desire tosecure by Letters Patent, is-- 1. The runner-stone G, constructed with asurface for grinding, which is a segment of a sphere in any direction inwhich it may be intersected, in combination with the concave E, whichalso is of a shape to'conform to said runner=stone; the saidrunner-stone and conca ve being arranged and operated substantially inthe nltm ner and for the purpose described.

2. The arrangement of the platform D, concave stone E, clamp-screws c c,and adjusting screws e e, in combination with the verticallyrevolvingrunner-stone G, substantially inthe manner, and'for the purposedescribed. i i v 3. The deflector 1:, applied substantially in themanner and for the purpose described.

' 4. Arranging the hopper so that its lower end rests upon the stone E,and connecting its upper end to the frame A, by books or fasteningswhich will allow it to descend 'or .rise with the stone E, substantiallyin the manner and for the purpose described.

I 5. The combination of the metal guards a, and clamp-screws c c, withthe runner-stone and concave, substantially in the manner and for thepurpose described.

. JOHN H BEAR.

Witnesses: I

Gnonen M. Sam-ran, Enrss LAW.

